The present invention relates to Air Cycle Machines (ACMs) and more specifically to seal plates for ACMs.
ACMs generally include a compressor section to compress air. The compressed air is discharged to a downstream heat exchanger and further routed to a turbine. The turbine extracts energy from the expanded air to drive the compressor. The air output from the turbine is generally utilized as an air supply for a vehicle, such as the cabin of an aircraft. ACMs can be used to achieve a desired pressure, temperature, and humidity in the air that is transferred to the environmental control system of the aircraft.
ACMs often have a three-wheel or four-wheel configuration. In a three-wheel ACM, a turbine drives both a compressor and a fan which rotate on a common shaft. In a four-wheel ACM, two turbine sections drive a compressor and a fan on a common shaft. In any configuration, airflow can be directed into the fan section and the compressor section. The airflow is then directed away from the compressor section towards the heat exchanger, from the heat exchanger to the turbine or turbines, and from the final turbine stage out of the ACM. ACMs can include seal plates that are disposed between the compressor section and the turbine section to reduce heat transfer between the compressor section and the turbine section. Seal plates can negatively reduce the power performance of ACMs as they can create drag on the rotating parts of ACMs.